Constant Modulus Algorithm (CMA) is only suited to balance the signals with modulus of the same value, but not suited to balance the high-order Quadrature Amplitude Modulation (QAM) signals. Combined with the virtues of CMA and Decision-Directed (DD) algorithm, an improved mixed blind equalization algorithm had been presented. First, the improved algorithm would make the system eye open using the CMA + DD parallel algorithm, and then switch to the DD algorithm to further reduce the residual error. The simulation results indicate that the improved algorithm has a very fast convergence speed, as well as a very small residual error for high-order QAM signals, and constellation recovery plan is very tight. Meanwhile, the improved algorithm can correct phase, and trace channel.%针对恒模算法(CMA)仅适用于模值为常数的信号,对高阶QAM信号的均衡效果差这一问题,结合CMA与判决引导(DD)算法各自的优点,提出一种CMA与DD算法相结合的改进混合型算法.在算法初期,利用CMA+DD并行算法使系统眼图睁开；然后,再转换到DD算法来进一步减小剩余误差.仿真结果表明,采用新算法对高阶信号均衡有较快的收敛速度和较小的剩余误差,星座图恢复很紧凑,并且改进算法能修正相位和跟踪信道.
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